MEDRADSC 1B03 Lecture Notes - Lecture 19: Arachnoid Granulation, Neural Tube Defect, Hydrocephalus
29 Jun 2016
School
Department
Course
Professor
Document Summary
A condition in which excess cerebrospinal fluid accumulates compressing brain tissue & blood vessels. Excess csp accumulates within the skull (production > absorption) Head enlarges since sutures in infancy have not yet close. Flow of csp through the ventricular system is blocked. Usually results from a fetal developmental abnormality (don"t have to memorize all: stenosis or neural tube defect, may be associated with myelomenigocele, or arachnoid-chiari malformation is present in many neonates. Obstructions leads to back pressure of fluid in the brain ventricles: enlarges ventricles, and compresses blood vessels and brain tissue. Absorption of csp through subarachnoid villi is impaired (can get through the arachnoid layer) Skull can expand to a certain degree to relieve pressure. If not treated, brain tissue is permanently damaged. Amount of brain damage depends on the rate of pressure increase and time of relief. Developmental abnormalities (narrowing of the __________: stenosis, atresia. Increased head circumference (measure the baseline of diameter)
